Driving method of display device and display device

ABSTRACT

The driving method provided by the present application includes: detecting a refresh frequency of a display device based on a plurality of predicted frames to obtain a change rule of the refresh frequency; obtaining a current refresh frequency of the display device and a corresponding frame number information; predicting an expected timing when the display device switches the refresh frequency next time and an expected frequency value after switching according to the change rule, the current refresh frequency, and the corresponding frame number information; and performing a gray-scale compensation on the display device according to the expected frequency value and the expected timing.

BACKGROUND OF DISCLOSURE Field of Disclosure

The present disclosure relates to the field of display technology, inparticular to a driving method of a display device and a display device.

Description of Prior Art

Generally, a refresh frequency of a display device is often fixed at acertain frequency when the display device is working. For example, amost common refresh frequency is 60 Hz. However, under certain specificconditions, it is often necessary for the display device to display at ahigher refresh frequency. Free-Sync technology allows a graphics cardand an accelerated processor to directly and dynamically control therefresh frequency of the display device connected.

For a display device equipped with the Free-Sync technology, a chargingtime for each frame of a highest refresh frequency and a charging timefor each frame of a lowest refresh frequency are the same, and onedifference is that blank times between the two kinds of frames aredifferent. Since a frame duration time corresponding to a low refreshfrequency is longer, a blank time thereof will be longer compared to ablank time corresponding to a high refresh frequency. However, too longof the blank time will deepen an impact of leakage on the display panel,and ultimately reduce overall brightness of the display panel. If thedisplay device is made to switch back and forth between the high and lowrefresh frequencies in a short time period according to a certain rule,a difference in brightness between different refresh frequencies willcause serious flicking on a display screen.

SUMMARY OF DISCLOSURE

A purpose of the present disclosure is to provide a driving method of adisplay device and a display device, which can prevent flickering of ascreen when switching a refresh frequency.

In a first aspect, the present disclosure provides a driving method of adisplay device, comprising following steps:

obtaining a plurality of predicted frames, and detecting a refreshfrequency of the display device based on the plurality of predictedframes to obtain a change rule of the refresh frequency;

obtaining a current refresh frequency of the display device and acorresponding frame number information when the display device displaysa target display frame;

predicting an expected timing when the display device switches therefresh frequency next time and an expected frequency value afterswitching according to the change rule, the current refresh frequency,and the corresponding frame number information; and

performing a gray-scale compensation on the display device according tothe expected frequency value and the expected timing,

wherein the step of predicting the expected timing when the displaydevice switches the refresh frequency next time and the expectedfrequency value after switching according to the change rule, thecurrent refresh frequency, and the corresponding frame numberinformation comprises:

obtaining the expected frequency value after switching according to thechange rule and the current refresh frequency;

obtaining remaining frame number information of the current refreshfrequency according to the change rule and the corresponding framenumber information; and

obtaining the expected timing for a next refresh frequency switchingaccording to the remaining frame number information,

wherein the step of performing the gray-scale compensation on thedisplay device according to the expected frequency value and theexpected timing comprises:

querying a gray-scale compensation table according to the expectedfrequency value to obtain a corresponding gray-scale compensation value;and

performing the gray-scale compensation on the display device at theexpected timing according to the gray-scale compensation value.

In the driving method provided by the present disclosure, the step ofobtaining the plurality of predicted frames, and detecting the refreshfrequency of the display device based on the plurality of predictedframes to obtain the change rule of the refresh frequency comprises:

obtaining the plurality of predicted frames, and performing a real-timedetection on the refresh frequency when the plurality of predictedframes are played on the display device to obtain a plurality offrequency values of the refresh frequency; and

detecting a number of continuous frames of each of the frequency valuesthrough a frequency prediction signal to obtain the number of continuousframes corresponding to each of the frequency values.

In the driving method provided by the present disclosure, the step ofobtaining the plurality of predicted frames, and performing thereal-time detection on the refresh frequency when the plurality ofpredicted frames are played on the display device to obtain theplurality of frequency values of the refresh frequency comprises:

obtaining the plurality of predicted frames and playing on the displaydevice; and

performing the real-time detection of the refresh frequency of thedisplay device to obtain the plurality of frequency values of therefresh frequency after playback continues for a first preset timeperiod.

In the driving method provided by the present disclosure, the step ofdetecting the number of continuous frames of each of the frequencyvalues through the frequency prediction signal to obtain the number ofcontinuous frames corresponding to each of the frequency valuescomprises:

performing a plurality times of detection on the number of continuousframes of each of the frequency values through the frequency predictionsignal to obtain a plurality of numbers of continuous framescorresponding to each of the frequency values; and

calculating an actual number of continuous frames corresponding to eachof the frequency values according to the plurality of numbers ofcontinuous frames.

In the driving method provided by the present disclosure, the step ofperforming the gray-scale compensation on the display device at theexpected timing according to the gray-scale compensation valuecomprises:

querying the gray-scale compensation table according to the expectedfrequency value to obtain the corresponding gray-scale compensationvalue;

obtaining a prediction of the expected timing when the next refreshfrequency switching occurs;

obtaining a target gray-scale compensation value according to theprediction and the gray-scale compensation value; and

performing the gray-scale compensation on the display device accordingto the target gray-scale compensation value when the refresh frequencyis switched.

In the driving method provided by the present disclosure, the step ofobtaining the target gray-scale compensation value according to theprediction and the gray-scale compensation value comprises:

if the expected timing is earlier than an actual refresh frequencyswitching timing, and a frequency value before switching is less thanthe expected frequency value after switching, the gray-scalecompensation value is optimized according to a first compensationcoefficient X1 to obtain the target gray-scale compensation value, andX1 is greater than 1; and

if the expected timing is later than the actual refresh frequencyswitching timing, and the frequency value before switching is less thanthe frequency value after switching, the gray-scale compensation valueis optimized according to a second compensation coefficient X2 to obtainthe target gray-scale compensation value, and X2 is less than 1 andgreater than 0.

In the driving method provided by the present disclosure, the step ofobtaining the target gray-scale compensation value according to theprediction and the gray-scale compensation value further comprises:

if the expected timing is equal to the actual refresh frequencyswitching timing, the gray-scale compensation value is used as thetarget gray-scale compensation value.

In a second aspect, the present disclosure provides a driving method ofa display device, which comprises following steps:

obtaining a plurality of predicted frames, and detecting a refreshfrequency of the display device based on the plurality of predictedframes to obtain a change rule of the refresh frequency;

obtaining a current refresh frequency of the display device and acorresponding frame number information when the display device displaysa target display frame;

predicting an expected timing when the display device switches therefresh frequency next time and an expected frequency value afterswitching according to the change rule, the current refresh frequency,and the corresponding frame number information; and

performing a gray-scale compensation on the display device according tothe expected frequency value and the expected timing.

In the driving method provided by the present disclosure, the step ofobtaining the plurality of predicted frames, and detecting the refreshfrequency of the display device based on the plurality of predictedframes to obtain the change rule of the refresh frequency comprises:

obtaining the plurality of predicted frames, and performing a real-timedetection on the refresh frequency when the plurality of predictedframes are played on the display device to obtain a plurality offrequency values of the refresh frequency; and

detecting a number of continuous frames of each of the frequency valuesthrough a frequency prediction signal to obtain the number of continuousframes corresponding to each of the frequency values.

In the driving method provided by the present disclosure, the step ofobtaining the plurality of predicted frames, and detecting the refreshfrequency of the display device based on the plurality of predictedframes to obtain the change rule of the refresh frequency comprises:

obtaining the plurality of predicted frames, and performing a real-timedetection on the refresh frequency when the plurality of predictedframes are played on the display device to obtain a plurality offrequency values of the refresh frequency; and

detecting a number of continuous frames of each of the frequency valuesthrough a frequency prediction signal to obtain the number of continuousframes corresponding to each of the frequency values.

In the driving method provided by the present disclosure, the step ofobtaining the plurality of predicted frames, and performing thereal-time detection on the refresh frequency when the plurality ofpredicted frames are played on the display device to obtain theplurality of frequency values of the refresh frequency comprises:

obtaining the plurality of predicted frames and playing on the displaydevice; and

performing the real-time detection of the refresh frequency of thedisplay device to obtain the plurality of frequency values of therefresh frequency after playback continues for a first preset timeperiod.

In the driving method provided by the present disclosure, the step ofdetecting the number of continuous frames of each of the frequencyvalues through the frequency prediction signal to obtain the number ofcontinuous frames corresponding to each of the frequency valuescomprises:

performing a plurality times of detection on the number of continuousframes of each of the frequency values through the frequency predictionsignal to obtain a plurality of numbers of continuous framescorresponding to each of the frequency values; and

In the driving method provided by the present disclosure, the step ofpredicting the expected timing when the display device switches therefresh frequency next time and the expected frequency value afterswitching according to the change rule, the current refresh frequency,and the corresponding frame number information comprises:

obtaining the expected frequency value after switching according to thechange rule and the current refresh frequency;

obtaining remaining frame number information of the current refreshfrequency according to the change rule and the corresponding framenumber information; and

obtaining the expected timing for a next refresh frequency switchingaccording to the remaining frame number information.

In the driving method provided by the present disclosure, the step ofperforming the gray-scale compensation on the display device accordingto the expected frequency value and the expected timing comprises:

querying a gray-scale compensation table according to the expectedfrequency value to obtain a corresponding gray-scale compensation value;and

performing the gray-scale compensation on the display device at theexpected timing according to the gray-scale compensation value.

In the driving method provided by the present disclosure, the step ofperforming the gray-scale compensation on the display device at theexpected timing according to the gray-scale compensation valuecomprises:

querying a gray-scale compensation table according to the expectedfrequency value to obtain a corresponding gray-scale compensation value;

obtaining a prediction of the expected timing when a next refreshfrequency switching occurs;

obtaining a target gray-scale compensation value according to theprediction and the gray-scale compensation value; and

performing the gray-scale compensation on the display device accordingto the target gray-scale compensation value when the refresh frequencyis switched.

In the driving method provided by the present disclosure, the step ofobtaining the target gray-scale compensation value according to theprediction and the gray-scale compensation value comprises:

if the expected timing is earlier than an actual refresh frequencyswitching timing, and a frequency value before switching is less thanthe expected frequency value after switching, the gray-scalecompensation value is optimized according to a first compensationcoefficient X1 to obtain the target gray-scale compensation value, andX1 is greater than 1; and

if the expected timing is later than the actual refresh frequencyswitching timing, and the frequency value before switching is less thanthe frequency value after switching, the gray-scale compensation valueis optimized according to a second compensation coefficient X2 to obtainthe target gray-scale compensation value, and X2 is less than 1 andgreater than 0.

In the driving method provided by the present disclosure, the step ofobtaining the target gray-scale compensation value according to theprediction and the gray-scale compensation value further comprises:

if the expected timing is equal to the actual refresh frequencyswitching timing, the gray-scale compensation value is used as thetarget gray-scale compensation value.

In a third aspect, the present disclosure provides a display device,which comprises:

a first detection module is configured to obtain a plurality ofpredicted frames, and detect a refresh frequency of the display devicebased on the plurality of predicted frames to obtain a change rule ofthe refresh frequency;

an acquisition module configured to obtain a current refresh frequencyof the display device and a corresponding frame number information whenthe display device displays a target display frame;

a prediction module configured to predict an expected timing when thedisplay device switches the refresh frequency next time and an expectedfrequency value after switching according to the change rule, thecurrent refresh frequency, and the corresponding frame numberinformation; and

a compensation module configured to perform a gray-scale compensation onthe display device according to the expected frequency value and theexpected timing.

In the display device provided by the present disclosure, the firstdetection module specifically comprises:

obtaining the plurality of predicted frames, and performing a real-timedetection on the refresh frequency when the plurality of predictedframes are played on the display device to obtain a plurality offrequency values of the refresh frequency; and

detecting a number of continuous frames of each of the frequency valuesthrough a frequency prediction signal to obtain the number of continuousframes corresponding to each of the frequency values.

In the display device provided by the present disclosure, the predictionmodule specifically comprises:

obtaining the expected frequency value after switching according to thechange rule and the current refresh frequency;

obtaining remaining frame number information of the current refreshfrequency according to the change rule and the corresponding framenumber information; and

obtaining the expected timing for a next refresh frequency switchingaccording to the remaining frame number information.

In the display device provided in the present disclosure, thecompensation module specifically comprises:

querying a gray-scale compensation table according to the expectedfrequency value to obtain a corresponding gray-scale compensation value;and

performing the gray-scale compensation on the display device at theexpected timing according to the gray-scale compensation value.

In the driving method of the display device and the display deviceprovided by the present disclosure, the plurality of predicted framesare inputted, and the refresh frequency of the display device aredetected based on the plurality of predicted frames to obtain the changerule of the refresh frequency; when the display device displays thetarget display frame, the current refresh frequency of the displaydevice and the corresponding frame number information are obtained; theexpected timing when the display device switches the refresh frequencynext time and the expected frequency value after switching are predictedaccording to the change rule, the current refresh frequency, and thecorresponding frame number information; and the gray-scale compensationis performed on the display device according to the expected frequencyvalue and the expected timing. Therefore, an advance prediction offrequency switching is realized, and then an advance calculation of thegray-scale compensation value is realized, which can prevent flickingcaused when the refresh frequency changes.

DESCRIPTION OF DRAWINGS

In order to more clearly explain the technical solutions in theembodiments of the present disclosure, the following will brieflyintroduce the drawings required in the description of the embodiments.Obviously, the drawings in the following description are only someembodiments of the present disclosure. For those skilled in the art,without paying any creative work, other drawings can be obtained basedon these drawings.

FIG. 1 is a schematic flowchart of a driving method of a display deviceprovided by an embodiment of the present disclosure.

FIGS. 2a to 2c are schematic diagrams of comparison of brightnesswaveforms of the driving method of the display device provided by theembodiment of the present disclosure.

FIG. 3 is a detection timing diagram of the driving method of thedisplay device provided by the embodiment of the present disclosure.

FIG. 4 is a specific schematic flowchart of the driving method of thedisplay device provided by the embodiment of the present disclosure.

FIG. 5 is a schematic structural diagram of a display device provided byan embodiment of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Technical solutions in the embodiments of the present disclosure will beclearly and completely described below in conjunction with drawings inthe embodiments of the present disclosure. Obviously, the describedembodiments are only a part of embodiments of the present disclosure,rather than all the embodiments. Based on the embodiments in the presentdisclosure, all other embodiments obtained by those skilled in the artwithout creative work fall within the protection scope of the presentdisclosure.

Please refer to FIG. 1, which is a schematic flowchart of a drivingmethod of a display device provided by an embodiment of the presentdisclosure. The driving method is used in the display device, and thedisplay device may be an organic light-emitting display or a liquidcrystal display, apparently, it may also be other common displaydevices. Wherein, the driving method comprises following steps:

S101, obtaining a plurality of predicted frames, and detecting a refreshfrequency of the display device based on the plurality of predictedframes to obtain a change rule of the refresh frequency.

S102, obtaining a current refresh frequency of the display device and acorresponding frame number information when the display device displaysa target display frame.

S103, predicting an expected timing when the display device switches therefresh frequency next time and an expected frequency value afterswitching according to the change rule, the current refresh frequency,and the corresponding frame number information.

S104, performing a gray-scale compensation on the display deviceaccording to the expected frequency value and the expected timing.

In the driving method of the display device provided by the embodimentof the present disclosure, the plurality of predicted frames areinputted, and the refresh frequency of the display device are detectedbased on the plurality of predicted frames to obtain the change rule ofthe refresh frequency; when the display device displays the targetdisplay frame, the current refresh frequency of the display device andthe corresponding frame number information are obtained; the expectedtiming when the display device switches the refresh frequency next timeand the expected frequency value after switching are predicted accordingto the change rule, the current refresh frequency, and the correspondingframe number information; and the gray-scale compensation is performedon the display device according to the expected frequency value and theexpected timing. Therefore, an advance prediction of frequency switchingis realized, and then an advance calculation of a gray-scalecompensation value is realized, which can prevent flicking caused whenthe refresh frequency changes.

For example, please refer to FIGS. 2a-2c . FIGS. 2a-2c are schematicdiagrams of comparison of brightness waveforms of the driving method ofthe display device provided by the embodiment of the present disclosure.As shown in FIGS. 2a-2c , FIG. 2a shows a brightness waveform whenswitching between different frequencies. It can be seen that frames aredensely arranged in high-frequency periods and overall brightness ishigher; and frames are sparsely arranged in low-frequency periods, andthe overall brightness is lower. Moreover, leakage of electricity willcause great fluctuations in brightness, and a screen of the displaydevice flickers seriously at this time. Therefore, a gray-scalecompensation table can be set to increase gray-scales in thelow-frequency periods to compensate for brightness difference betweenlow-frequency regions and high-frequency regions. At present, afrequency adjustment range of mainstream display devices is from 48 Hzto 240 Hz, and some key frequencies are selected therefrom to setcompensation binding points, and remaining frequencies are obtained byinterpolation from the gray-scale compensation table.

In actual work of the display device, a frame frequency can be detectedafter a current frame transmission is completed. If no other processingis done, no new gray-scale compensation will be applied to a first frameafter switching from a high-frequency to a low-frequency, and alow-frequency gray-scale compensation will be applied to a first frameafter switching from the low-frequency to the high-frequency. In thisway, as shown in FIG. 2b , brightness spikes will appear when switchingbetween different frequencies due to inability to detect frequencies inadvance. If a frequency switching signal can be obtained in advance, itcan smoothly provide a suitable gray-scale for the first frame after thefrequency switching, as shown in FIG. 2c . that is, the driving methodprovided by the embodiment of the present disclosure can realize theadvance prediction of the frequency switching, thereby realizing advancecalculation of the gray-scale compensation value, which can preventflicking caused when the refresh frequency changes.

Specifically, in the step S101, the plurality of predicted frames, thatis, images used to detect the change rule of the refresh frequency ofthe display device, are pre-stored in a memory of the display device.When it is detected that the display device is powered on, the pluralityof predicted frames in the memory are automatically extracted andplayed, so as to realize detection of the change rule of a screenrefresh chip.

Wherein, the change rule of the refresh frequency comprises allfrequency values of the refresh frequency of the display device and asequence thereof, and a number of continuous frames or a duration timeof each frequency value. For example, the frequency values are sorted bytime as a1, a2, a3, a4, and a5. When it is detected that the frequencyvalue is a2, the frequency value after next switching is a3.

Wherein, in some embodiments, the step S101 may specifically comprisefollowing sub-steps:

S1011, obtaining the plurality of predicted frames, and performing areal-time detection on the refresh frequency when the plurality ofpredicted frames are played on the display device, so as to obtain aplurality of frequency values of the refresh frequency; and S1012,detecting the number of continuous frames of each frequency valuethrough a frequency prediction signal to obtain the number of continuousframes corresponding to each frequency value.

Wherein, the step S1011 may specifically comprise: obtaining theplurality of predicted frames and playing on the display device; andafter playback continues for a first preset time period, performing thereal-time detection of the refresh frequency of the display device toobtain the plurality of frequency values of the refresh frequency.

Wherein, when the refresh frequency starts to change, generallyspeaking, the refresh frequency starts to change after a certain timeperiod after starting to play the plurality of predicted frames. Afterthe first preset time period, the refresh frequency gradually changesfrom irregular changes to regular changes and tends to be stable.Therefore, counting starts at this time to detect a number of changedfrequency values and corresponding frequency values. After two times ofswitching are completed at different frequency values, determination canbe made, and the number of the changed frequency values and thecorresponding frequency values can be obtained.

Wherein, in the step S1012, the frequency prediction signal detects thenumber of continuous frames of each frequency value to obtain the numberof continuous frames corresponding to each frequency value. Apparently,it can also be converted into corresponding times. In some embodiments,in order to improve accuracy of the number of continuous framescorresponding to each frequency value, following steps may be adopted:performing a plurality times of detection on the number of continuousframes of each frequency value through the frequency prediction signalto obtain a plurality of numbers of continuous frames corresponding toeach frequency value; and calculating an actual number of continuousframes corresponding to each frequency value according to the pluralityof numbers of continuous frames. For example, it is possible to performN times of detection, and then average the numbers of continuous framesobtained from each detection to calculate the actual number ofcontinuous frames.

Specifically, please refer to FIGS. 3 and 4 at the same time. FIG. 3 isa detection timing diagram of the driving method of the display deviceprovided in the embodiment of the present disclosure, and FIG. 4 is aspecific schematic flowchart of the driving method of the display deviceprovided in the embodiment of the present disclosure. As shown in FIGS.3 and 4, a frequency detection signal xh1 is inputted, and when it isdetected that the refresh frequency starts to change, a change ruledetection is prepared. When the frequency detection signal xh1 lasts fora first preset time period Tx1, an enable signal xh2 of change ruledetection function is pulled high, and the change rule detection starts.When it is detected that the refresh frequency changes again, an xh3 ispulled high, and after two times of switching at different frequencyvalues are completed, the number of changed frequency values and thecorresponding frequency values can be obtained. Then an xh4 is pulledhigh, and then a frequency prediction signal xh5 is used to detect thenumber of continuous frames corresponding to each frequency value. Whenit is detected that the predicted frames have been played (that is,within a second preset time period Tx2, and the refresh frequency is nolonger switched), the detection can be stopped, and the numbers ofcontinuous frames corresponding to a set of frequency values can beobtained.

Wherein, in the step S102, the target display frame refers to an imageactually to be played when a user turns on the display device. Wherein,the current refresh frequency refers to a refresh frequency when thegray-scale compensation is started after an image starts to be played.Wherein, the frame number information refers to a frequency valuecorresponding to the current refresh frequency, a number of continuousframes corresponding to the frequency value, and a number of frames thathave been played at a current frequency value.

Wherein, in the step S103, according to the change rule of the refreshfrequency detected in the step S101, as well as the current refreshfrequency and the corresponding frame number information, the expectedtiming for a next refresh frequency switching and the expect frequencyvalue after switching can be calculated. For example, the currentfrequency value is a1, which has b frames in total. According to thechange rule, it can be known that the frequency value after thefrequency value a1 is a2. The current frequency value corresponds to atotal of b frames, and b1 frames have already been played. Therefore, itcan be calculated that there are b-b1 frames to be played to update anext refresh frequency, and then the expected timing for the nextrefresh frequency switching can be known.

Wherein, in the step S104, a method of querying the gray-scalecompensation table may be adopted to obtain a gray-scale compensationvalue corresponding to each frequency value. Wherein, the gray-scalecompensation table is calculated through multiple experiments inadvance. Wherein, an adjustment range of the refresh frequency is 48 Hzto 240 Hz. It is possible to select several key frequency points to setbinding points, that is, to test the gray-scale compensation valuescorresponding to the several key frequency points, and then thegray-scale compensation values corresponding to remaining frequenciescan be calculated through interpolation. Wherein, if the display deviceis a liquid crystal display device, the gray-scale compensation can beperformed by adjusting brightness of a backlight of the display device.If the display device is an organic light-emitting display device, thegray-scale compensation can be performed by adjusting a current drivingmethod of corresponding anodes.

In some embodiments, the step S104 may comprise following sub-steps:S1041, querying the gray-scale compensation table according to theexpected frequency value to obtain a corresponding gray-scalecompensation value; and S1042, performing the gray-scale compensation onthe display device at the expected timing according to the gray-scalecompensation value. Wherein, the expected frequency value has thecorresponding gray-scale compensation value in the gray-scalecompensation table, which can be obtained by looking up the table. Then,at the expected timing, the gray-scale compensation value is used toperform the gray-scale compensation on the display device.

Apparently, due to errors in prediction of frequency switching timing,the above compensation method may have errors.

In some embodiments, the step S104 may comprise following sub-steps:S1043, querying the gray-scale compensation table according to theexpected frequency value to obtain the corresponding gray-scalecompensation value; S1044, when the next refresh frequency switchingoccurs, obtaining a prediction of the expected timing; S1045, obtaininga target gray-scale compensation value according to the prediction andthe gray-scale compensation value; and S1046, performing the gray-scalecompensation on the display device according to the target gray-scalecompensation value when the refresh frequency is switched.

Wherein, in the step S1043, the expected frequency value has thecorresponding gray-scale compensation value in the gray-scalecompensation table, which can be obtained by looking up the table. Inthe step S1044, the prediction indicates whether the frequency switchingtiming is earlier than the expected timing or later than the expectedtiming, or just happens to be accurate.

In the step S1045, if the expected timing is earlier than an actualrefresh frequency switching timing, and a frequency value beforeswitching is less than the expected frequency value after switching, thegray-scale compensation value is optimized according to a firstcompensation coefficient X1 to obtain the target gray-scale compensationvalue, and X1 is greater than 1. Wherein, the target gray-scalecompensation value H is X1 multiplied by the look-up table to obtain thegray-scale compensation value. Apparently, for this situation, a numberof predicted frames is adjusted according to a relatively highproportion after ten times of switching, so as to update the change rulein real time, that is, to adjust the number of continuous framescorresponding to each frequency value.

If the expected timing is later than the actual refresh frequencyswitching timing, and the frequency value before switching is less thanthe frequency value after switching, the gray-scale compensation valueis optimized according to a second compensation coefficient X2 to obtainthe target gray-scale compensation value, and X2 is less than 1 andgreater than 0. Apparently, for this situation, the number of predictedframes is adjusted according to the relatively high proportion after tentimes of switching, so as to update the change rule in real time, thatis, to adjust the number of continuous frames corresponding to eachfrequency value.

Wherein, the target gray-scale compensation value H is X2 multiplied bythe look-up table to obtain the gray-scale compensation value. If theexpected timing is equal to the actual refresh frequency switchingtiming, the gray-scale compensation value is used as the targetgray-scale compensation value.

In the driving method provided by the embodiments of the presentdisclosure, the plurality of predicted frames are obtained, and therefresh frequency of the display device are detected based on theplurality of predicted frames to obtain the change rule of the refreshfrequency; when the display device displays the target display frame,the current refresh frequency of the display device and thecorresponding frame number information are obtained; the expected timingwhen the display device switches the refresh frequency next time and theexpected frequency value after switching are predicted according to thechange rule, the current refresh frequency, and the corresponding framenumber information; and the gray-scale compensation is performed on thedisplay device according to the expected frequency value and theexpected timing. Therefore, the advance prediction of the frequencyswitching is realized, and then the advance calculation of thegray-scale compensation value is realized, which can prevent flickingcaused when the refresh frequency changes.

Please refer to FIG. 5, which is a schematic structural diagram of adisplay device provided by an embodiment of the present disclosure. Thedisplay device comprises: a first detection module 201, an acquisitionmodule 202, a prediction module 203, and a compensation module 204.

Wherein, the first detection module 201 is configured to input aplurality of predicted frames, and detect a refresh frequency of thedisplay device based on the plurality of predicted frames, so as toobtain a change rule of the refresh frequency. The plurality ofpredicted frames, that is, images used to detect the change rule of therefresh frequency of the display device, are pre-stored in a memory ofthe display device. When it is detected that the display device ispowered on, the plurality of predicted frames in the memory areautomatically extracted and played, so as to realize detection of thechange rule of a screen refresh chip. Wherein, the change rule of therefresh frequency comprises all frequency values of the refreshfrequency of the display device and a sequence thereof, a number ofcontinuous frames or a duration time of each frequency value. Forexample, the frequency values are sorted by time as a1, a2, a3, a4, anda5. When it is detected that the frequency value is a2, the frequencyvalue after next switching is a3.

Wherein, in some embodiments, the first detection module 201 isconfigured to: obtain the plurality of predicted frames and perform areal-time detection on the refresh frequency when the display deviceplays the plurality of predicted frames to obtain a plurality offrequency values of the refresh frequency; and detect the number ofcontinuous frames of each frequency value through a frequency predictionsignal to obtain the number of continuous frames corresponding to eachfrequency value. Wherein, it may specifically comprise: obtaining theplurality of predicted frames and playing on the display device; andafter playback continues for a first preset time period, performing thereal-time detection of the refresh frequency of the display device toobtain the plurality of frequency values of the refresh frequency.

Wherein, when the refresh frequency starts to change, generallyspeaking, the refresh frequency starts to change after a certain timeperiod after starting to play the plurality of predicted frames. Afterthe first preset time period, the refresh frequency gradually changesfrom irregular changes to regular changes and tends to be stable.Therefore, counting starts at this time to detect a number of changedfrequency values and corresponding frequency values. After two times ofswitching are completed at different frequency values, determination canbe made, and the number of the changed frequency values and thecorresponding frequency values can be obtained.

Wherein, the frequency prediction signal detects the number ofcontinuous frames of each frequency value to obtain the number ofcontinuous frames corresponding to each frequency value. Apparently, itcan also be converted into corresponding times. In some embodiments, inorder to improve accuracy of the number of continuous framescorresponding to each frequency value, following steps may be adopted:performing a plurality times of detection on the number of continuousframes of each frequency value through the frequency prediction signalto obtain a plurality of numbers of continuous frames corresponding toeach frequency value; and calculating an actual number of continuousframes corresponding to each frequency value according to the pluralityof numbers of continuous frames. For example, it is possible to performN times of detection, and then average the numbers of continuous framesobtained from each detection to calculate the actual number ofcontinuous frames.

Wherein, the acquisition module 202 is configured to obtain a currentrefresh frequency of the display device and corresponding frame numberinformation when the display device displays a target display frame. Thetarget display frame refers to an image actually to be played when auser opens the display device. Wherein, the current refresh frequencyrefers to a refresh frequency when a gray-scale compensation is startedafter the image starts to be played. Wherein, the frame numberinformation refers to a frequency value corresponding to the currentrefresh frequency, a number of continuous frames corresponding to thefrequency value, and a number of frames that have been played at thecurrent frequency value.

Wherein, the prediction module 203 is configured to predict an expectedtiming when the display device switches the refresh frequency next timeand an expected frequency value after switching according to the changerule, the current refresh frequency, and the corresponding frame numberinformation. According to the change rule of the refresh frequencydetected, as well as the current refresh frequency and the correspondingframe number information, the expected timing for a next refreshfrequency switching and the expect frequency value after switching canbe calculated. For example, the current frequency value is a1, which hasb frames in total. According to the change rule, it can be known thatthe frequency value after the frequency value a1 is a2. The currentfrequency value corresponds to a total of b frames, and b1 frames havealready been played. Therefore, it can be calculated that there are b-b1frames to be played to update a next refresh frequency, and then theexpected timing of the next frequency switching can be known.

Wherein, the compensation module 204 is configured to perform thegray-scale compensation on the display device according to the expectedfrequency value and the expected timing. The compensation module 204 mayquery a gray-scale compensation table to obtain the gray-scalecompensation value corresponding to each frequency value. Wherein, thegray-scale compensation table is calculated through multiple experimentsin advance. Wherein, an adjustment range of the refresh frequency is 48Hz to 240 Hz. It is possible to select several key frequency points toset binding points, that is, to test the gray-scale compensation valuescorresponding to the several key frequency points, and then thegray-scale compensation values corresponding to remaining frequenciescan be calculated through interpolation. Wherein, if the display deviceis a liquid crystal display device, the gray-scale compensation can beperformed by adjusting brightness of a backlight of the display device.If the display device is an organic light emitting display device, thegray-scale compensation can be performed by adjusting a current drivingmethod of corresponding anodes.

In some embodiments, the compensation module 204 is specificallyconfigured to: query the gray-scale compensation table according to theexpected frequency value to obtain a corresponding gray-scalecompensation value; and perform the gray-scale compensation on thedisplay device at the expected timing according to the gray-scalecompensation value. Wherein, the expected frequency value has thecorresponding gray-scale compensation value in the gray-scalecompensation table, which can be obtained by looking up the table. Then,at the expected timing, the gray-scale compensation value is used toperform the gray-scale compensation on the display device.

Apparently, due to errors in prediction of the frequency switchingtiming, the above compensation method may have errors.

In some embodiments, the compensation module 204 is specificallyconfigured to: query the gray-scale compensation table according to theexpected frequency value to obtain the corresponding gray-scalecompensation value; when the next refresh frequency switching occurs,obtain a prediction of the expected timing; obtain a target gray-scalecompensation value according to the prediction and the gray-scalecompensation value; and perform the gray-scale compensation on thedisplay device according to the target gray-scale compensation valuewhen the refresh frequency is switched. Wherein, the expected frequencyvalue has the corresponding gray-scale compensation value in thegray-scale compensation table, which can be obtained by looking up thetable. The prediction situation indicates that whether the frequencyswitching timing is earlier than the expected timing or later than theexpected timing, or just happens to be accurate. If the expected timingis earlier than an actual refresh frequency switching timing, and afrequency value before switching is less than the expected frequencyvalue after switching, the gray-scale compensation value is optimizedaccording to a first compensation coefficient X1 to obtain the targetgray-scale compensation value, and X1 is greater than 1. Wherein, thetarget gray-scale compensation value H is X1 multiplied by the look-uptable to obtain the gray-scale compensation value. Apparently, for thissituation, a number of predicted frames is adjusted according to arelatively high proportion after ten times of switching, so as to updatethe change rule in real time, that is, to adjust the number ofcontinuous frames corresponding to each frequency value.

If the expected timing is later than the actual refresh frequencyswitching timing, and the frequency value before switching is less thanthe frequency value after switching, the gray-scale compensation valueis optimized according to a second compensation coefficient X2 to obtainthe target gray-scale compensation value, and X2 is less than 1 andgreater than 0. Apparently, for this situation, the number of predictedframes is adjusted according to a relatively high proportion after tentimes of switching, so as to update the change rule in real time, thatis, to adjust the number of continuous frames corresponding to eachfrequency value.

Wherein, the target gray-scale compensation value H is X2 multiplied bythe look-up table to obtain the gray-scale compensation value. If theexpected timing is equal to the actual refresh frequency switchingtiming, the gray-scale compensation value is used as the targetgray-scale compensation value.

In the display device provided by the embodiment of the presentdisclosure, the plurality of predicted frames are inputted, and therefresh frequency of the display device are detected based on theplurality of predicted frames to obtain the change rule of the refreshfrequency; when the display device displays the target display frame,the current refresh frequency of the display device and thecorresponding frame number information are obtained; the expected timingwhen the display device switches the refresh frequency next time and theexpected frequency value after switching are predicted according to thechange rule, the current refresh frequency, and the corresponding framenumber information; and the gray-scale compensation is performed on thedisplay device according to the expected frequency value and theexpected timing. Therefore, the advance prediction of the frequencyswitching is realized, and then the advance calculation of thegray-scale compensation value is realized, which can prevent flickingcaused when the refresh frequency changes.

What is claimed is:
 1. A driving method of a display device, comprisingfollowing steps: obtaining a plurality of predicted frames, anddetecting a refresh frequency of the display device based on theplurality of predicted frames to obtain a change rule of the refreshfrequency; obtaining a current refresh frequency of the display deviceand a corresponding frame number information when the display devicedisplays a target display frame; predicting an expected timing when thedisplay device switches the refresh frequency next time and an expectedfrequency value after switching according to the change rule, thecurrent refresh frequency, and the corresponding frame numberinformation; and performing a gray-scale compensation on the displaydevice according to the expected frequency value and the expectedtiming, wherein the step of predicting the expected timing when thedisplay device switches the refresh frequency next time and the expectedfrequency value after switching according to the change rule, thecurrent refresh frequency, and the corresponding frame numberinformation comprises: obtaining the expected frequency value afterswitching according to the change rule and the current refreshfrequency; obtaining remaining frame number information of the currentrefresh frequency according to the change rule and the correspondingframe number information; and obtaining the expected timing for a nextrefresh frequency switching according to the remaining frame numberinformation, wherein the step of performing the gray-scale compensationon the display device according to the expected frequency value and theexpected timing comprises: querying a gray-scale compensation tableaccording to the expected frequency value to obtain a correspondinggray-scale compensation value; and performing the gray-scalecompensation on the display device at the expected timing according tothe gray-scale compensation value.
 2. The driving method according toclaim 1, wherein the step of obtaining the plurality of predictedframes, and detecting the refresh frequency of the display device basedon the plurality of predicted frames to obtain the change rule of therefresh frequency comprises: obtaining the plurality of predictedframes, and performing a real-time detection on the refresh frequencywhen the plurality of predicted frames are played on the display deviceto obtain a plurality of frequency values of the refresh frequency; anddetecting a number of continuous frames of each of the frequency valuesthrough a frequency prediction signal to obtain the number of continuousframes corresponding to each of the frequency values.
 3. The drivingmethod according to claim 2, wherein the step of obtaining the pluralityof predicted frames, and performing the real-time detection on therefresh frequency when the plurality of predicted frames are played onthe display device to obtain the plurality of frequency values of therefresh frequency comprises: obtaining the plurality of predicted framesand playing on the display device; and performing the real-timedetection of the refresh frequency of the display device to obtain theplurality of frequency values of the refresh frequency after playbackcontinues for a first preset time period.
 4. The driving methodaccording to claim 2, wherein the step of detecting the number ofcontinuous frames of each of the frequency values through the frequencyprediction signal to obtain the number of continuous framescorresponding to each of the frequency values comprises: performing aplurality times of detection on the number of continuous frames of eachof the frequency values through the frequency prediction signal toobtain a plurality of numbers of continuous frames corresponding to eachof the frequency values; and calculating an actual number of continuousframes corresponding to each of the frequency values according to theplurality of numbers of continuous frames.
 5. The driving methodaccording to claim 1, wherein the step of performing the gray-scalecompensation on the display device at the expected timing according tothe gray-scale compensation value comprises: querying the gray-scalecompensation table according to the expected frequency value to obtainthe corresponding gray-scale compensation value; obtaining a predictionof the expected timing when the next refresh frequency switching occurs;obtaining a target gray-scale compensation value according to theprediction and the gray-scale compensation value; and performing thegray-scale compensation on the display device according to the targetgray-scale compensation value when the refresh frequency is switched. 6.The driving method according to claim 5, wherein the step of obtainingthe target gray-scale compensation value according to the prediction andthe gray-scale compensation value comprises: if the expected timing isearlier than an actual refresh frequency switching timing, and afrequency value before switching is less than the expected frequencyvalue after switching, the gray-scale compensation value is optimizedaccording to a first compensation coefficient X1 to obtain the targetgray-scale compensation value, and X1 is greater than 1; and if theexpected timing is later than the actual refresh frequency switchingtiming, and the frequency value before switching is less than thefrequency value after switching, the gray-scale compensation value isoptimized according to a second compensation coefficient X2 to obtainthe target gray-scale compensation value, and X2 is less than 1 andgreater than
 0. 7. The driving method according to claim 6, wherein thestep of obtaining the target gray-scale compensation value according tothe prediction and the gray-scale compensation value further comprises:if the expected timing is equal to the actual refresh frequencyswitching timing, the gray-scale compensation value is used as thetarget gray-scale compensation value.
 8. A driving method of a displaydevice, which comprises following steps: obtaining a plurality ofpredicted frames, and detecting a refresh frequency of the displaydevice based on the plurality of predicted frames to obtain a changerule of the refresh frequency; obtaining a current refresh frequency ofthe display device and a corresponding frame number information when thedisplay device displays a target display frame; predicting an expectedtiming when the display device switches the refresh frequency next timeand an expected frequency value after switching according to the changerule, the current refresh frequency, and the corresponding frame numberinformation; and performing a gray-scale compensation on the displaydevice according to the expected frequency value and the expectedtiming.
 9. The driving method according to claim 8, wherein the step ofobtaining the plurality of predicted frames, and detecting the refreshfrequency of the display device based on the plurality of predictedframes to obtain the change rule of the refresh frequency comprises:obtaining the plurality of predicted frames, and performing a real-timedetection on the refresh frequency when the plurality of predictedframes are played on the display device to obtain a plurality offrequency values of the refresh frequency; and detecting a number ofcontinuous frames of each of the frequency values through a frequencyprediction signal to obtain the number of continuous framescorresponding to each of the frequency values.
 10. The driving methodaccording to claim 9, wherein the step of obtaining the plurality ofpredicted frames, and performing the real-time detection on the refreshfrequency when the plurality of predicted frames are played on thedisplay device to obtain the plurality of frequency values of therefresh frequency comprises: obtaining the plurality of predicted framesand playing on the display device; and performing the real-timedetection of the refresh frequency of the display device to obtain theplurality of frequency values of the refresh frequency after playbackcontinues for a first preset time period.
 11. The driving methodaccording to claim 9, wherein the step of detecting the number ofcontinuous frames of each of the frequency values through the frequencyprediction signal to obtain the number of continuous framescorresponding to each of the frequency values comprises: performing aplurality times of detection on the number of continuous frames of eachof the frequency values through the frequency prediction signal toobtain a plurality of numbers of continuous frames corresponding to eachof the frequency values; and calculating an actual number of continuousframes corresponding to each of the frequency values according to theplurality of numbers of continuous frames.
 12. The driving methodaccording to claim 8, wherein the step of predicting the expected timingwhen the display device switches the refresh frequency next time and theexpected frequency value after switching according to the change rule,the current refresh frequency, and the corresponding frame numberinformation comprises: obtaining the expected frequency value afterswitching according to the change rule and the current refreshfrequency; obtaining remaining frame number information of the currentrefresh frequency according to the change rule and the correspondingframe number information; and obtaining the expected timing for a nextrefresh frequency switching according to the remaining frame numberinformation.
 13. The driving method according to claim 8, wherein thestep of performing the gray-scale compensation on the display deviceaccording to the expected frequency value and the expected timingcomprises: querying a gray-scale compensation table according to theexpected frequency value to obtain a corresponding gray-scalecompensation value; and performing the gray-scale compensation on thedisplay device at the expected timing according to the gray-scalecompensation value.
 14. The driving method according to claim 8, whereinthe step of performing the gray-scale compensation on the display deviceat the expected timing according to the gray-scale compensation valuecomprises: querying a gray-scale compensation table according to theexpected frequency value to obtain a corresponding gray-scalecompensation value; obtaining a prediction of the expected timing when anext refresh frequency switching occurs; obtaining a target gray-scalecompensation value according to the prediction and the gray-scalecompensation value; and performing the gray-scale compensation on thedisplay device according to the target gray-scale compensation valuewhen the refresh frequency is switched.
 15. The driving method accordingto claim 14, wherein the step of obtaining the target gray-scalecompensation value according to the prediction and the gray-scalecompensation value comprises: if the expected timing is earlier than anactual refresh frequency switching timing, and a frequency value beforeswitching is less than the expected frequency value after switching, thegray-scale compensation value is optimized according to a firstcompensation coefficient X1 to obtain the target gray-scale compensationvalue, and X1 is greater than 1; and if the expected timing is laterthan the actual refresh frequency switching timing, and the frequencyvalue before switching is less than the frequency value after switching,the gray-scale compensation value is optimized according to a secondcompensation coefficient X2 to obtain the target gray-scale compensationvalue, and X2 is less than 1 and greater than
 0. 16. The driving methodaccording to claim 15, wherein the step of obtaining the targetgray-scale compensation value according to the prediction and thegray-scale compensation value further comprises: if the expected timingis equal to the actual refresh frequency switching timing, thegray-scale compensation value is used as the target gray-scalecompensation value.
 17. A display device, which comprises: a firstdetection module is configured to obtain a plurality of predictedframes, and detect a refresh frequency of the display device based onthe plurality of predicted frames to obtain a change rule of the refreshfrequency; an acquisition module configured to obtain a current refreshfrequency of the display device and a corresponding frame numberinformation when the display device displays a target display frame; aprediction module configured to predict an expected timing when thedisplay device switches the refresh frequency next time and an expectedfrequency value after switching according to the change rule, thecurrent refresh frequency, and the corresponding frame numberinformation; and a compensation module configured to perform agray-scale compensation on the display device according to the expectedfrequency value and the expected timing.
 18. The display deviceaccording to claim 17, wherein the first detection module specificallycomprises: obtaining the plurality of predicted frames, and performing areal-time detection on the refresh frequency when the plurality ofpredicted frames are played on the display device to obtain a pluralityof frequency values of the refresh frequency; and detecting a number ofcontinuous frames of each of the frequency values through a frequencyprediction signal to obtain the number of continuous framescorresponding to each of the frequency values.
 19. The display deviceaccording to claim 17, wherein the prediction module specificallycomprises: obtaining the expected frequency value after switchingaccording to the change rule and the current refresh frequency;obtaining remaining frame number information of the current refreshfrequency according to the change rule and the corresponding framenumber information; and obtaining the expected timing for a next refreshfrequency switching according to the remaining frame number information.20. The display device according to claim 17, wherein the compensationmodule specifically comprises: querying a gray-scale compensation tableaccording to the expected frequency value to obtain a correspondinggray-scale compensation value; and performing the gray-scalecompensation on the display device at the expected timing according tothe gray-scale compensation value.